The website of the team who research palaeoenvironmental change at the Open University

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Palaeoecology

Orinoco Lake surrounded by diverse tropical vegetation.

We have research projects on both terrestrial and marine palaeoecology.

Terrestrial palaeoecology in the tropics

We explore past environmental change and human-vegetation-climate interaction so that we can better understand the Earth systems operating on our changing planet today. We specialise in a variety of techniques including fossil pollen, charcoal, chironomids (non-biting midges), non-pollen palynomorphs and pollen chemistry. These proxies can tell us information about past vegetation, fire, water quality and climate. However, this is by no means the full range of our activity!

Individual research projects within the terrestrial palaeoecology theme fit within four broad areas which seek to tackle key questions designed to improve our understanding of how the Earth’s systems function. We employ a variety of biological and chemical methods to help us reconstruct past environments and address these questions:

We investigate modern assemblages of planktonic foraminifera from surface ocean collected from sediment trap time-series (bi-weekly resolution) and benthic foraminifera (core-tops) and link it to the physical, chemical and biological factors that contributes to the changes in total planktonic foraminifera flux, species flux and benthic foraminiferal assemblage. The modern day quantification of species assemblages are applied at geological time scales to understand past changes in processes such as productivity, thermocline ventilation, temperature and oxygenation in the world's oceans.

In addition to the planktonic foraminifera species abundance which reflects species’ growth conditions, we investigate shell parameters (size and thickness) of planktonic foraminifera as a direct ecological response of changing physical, chemical and biological factors in seawater using recorded data during the sample collection. These variables are currently investigated to reflect ecological changes in planktonic foraminifera due to impact of ongoing ocean acidification in the north Atlantic subtropical gyre.

The epifaunal bivalve, Bositra radiata, an extreme opportunist that thrived during the onset of deoxygenation associated with the Toarcian (Jurassic) Oceanic Anoxic Event. (Field of view=8cm.)

Members of the team also have ongoing work on the benthic macro- and micro-fossil palaeoecology prior, during and after a major period of ocean de-oxygenation that occurred about 183 Ma ago in the Jurassic (see also ocean deoxygenation theme). The macrofossil benthic assemblages changed drastically during the event with only extreme opportunists surviving. We are currently working to reconstruct the terrestrial plant assemblage over this extreme event using the fossil palynomorph record preserved in shallow-marine sedimentary deposits.